Let's say that two processes which use flock both try and open the same file simultaneously. Only one of the processes will be able to lock it first. If that first process deletes the file and releases the lock then the second process will not be able to do anything to the deleted file. The second process will not read the nonexistent deleted file. It will not write it.

So there is that protection against race conditions. Only one process will access the file at a time, which is the purpose of having an exclusive lock.

In reply to Re: Re: Re: Re: correct usage of flock? by sierrathedog04
in thread correct usage of flock? by cLive ;-)

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